P1114

CIRCUIT DESCRIPTION
The Engine Coolant Temperature (ECT) sensor is a variable resistor, sometimes called a thermistor, that measures the temperature of the engine coolant. The Powertrain Control Module (PCM) supplies 5 volts to the ECT signal circuit. When the ECT is cold, the sensor resistance is high. When the ECT increases, the sensor resistance lowers. With high sensor resistance, the PCM detects a high voltage on the ECT signal circuit. With lower sensor resistance, the PCM detects a lower voltage on the ECT signal circuit. If the PCM detects an excessively low ECT signal voltage, which is a high temperature indication, this Diagnostic Trouble Code (DTC) will set.

CONDITIONS FOR RUNNING THE DTC
Engine run time is more than 3 seconds.

CONDITIONS FOR SETTING THE DTC
The PCM detects an intermittent ECT sensor temperature of more than 134°C (274°F).

ACTION TAKEN WHEN THE DTC SETS
^ The control module stores the DTC in history after the first failure but will not illuminate the Malfunction Indicator Lamp (MIL).
^ The control module records the operating conditions at the time the diagnostic fails. The control module stores the failure information in the scan tools Freeze Frame/Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
^ A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles.
^ A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the startup coolant temperature and the engine coolant temperature exceeds 70°C (160°F) during the same ignition cycle.
^ Use the scan tool Clear Information function.

DIAGNOSTIC AIDS
^ An intermittent short to ground in the ECT sensor signal circuit could result in a DTC P1114. If the low ECT voltage (high temperature) reading is present, additional sensor circuit voltage codes could be set. Refer to any non-intermittent DTCs that are set.
^ Use the Temperature vs. Resistance Value scale in order to test the coolant sensor at various temperature levels in order to evaluate the possibility of a skewed sensor. A skewed sensor could result in poor driveability complaints. Refer to Temperature vs Resistance. [1][2]Computers and Control Systems
^ If an intermittent condition is suspected, refer to Intermittent Conditions. Intermittent Conditions

TEST DESCRIPTION

Steps 1-9:

The number below refers to the step number on the diagnostic table.
5. If there is no driveability complaint associated with DTC and it does not reset, then system OK.